Abstract Representations of the chemical structures of dyes and fluorochromes often are used to illustrate staining mechanisms and histochemical reactions. Unfortunately, inaccurate chemical structures sometimes are used, which results in problems for teaching and research in histochemistry. We comment here on published examples of inadequate chemical drawing and modeling. In particular, omission of hydrogen atoms can lead to misleading hydrogen-bonding interactions, and inaccurate drawing and modeling procedures result in a variety of implausible molecular structures. The examples and arguments given here are easily intelligible for non-chemists and could be used as part of a training approach to help avoid publication of misleading or puzzling dye structures and molecular models for illustrating biological staining and histochemical studies.